Aim: this study was conducted to determine the distance between the mesio-incisal angles of maxillary central incisors along the midline to a line running between the tips of the maxillary canines (IC line) in Arab population with different arch forms.
Materials & Methods: 226 stone casts for selected dentate Saudi students were categorized, according to their morphological description, into three groups (ovoid, tapering, and square) arch forms. Using a digital caliper, the distances between the mesio-incisal angles of the maxillary central incisors along the midline to the IC line (AB distance) and to the midpoint between fovea palatine (AC distance) were measured. The data were collected and statistically analyzed.
Results: One way analysis of variance (ANOVA) showed that the mean of AB distance was affected significantly by change of the arch form and also for the AB: AC ratio where p< 0.001.
Conclusion: The fundamental results of this study can serve as a guide for determining the mesio-distal width of the maxillary anterior teeth in different arch forms.